Sound recording or reproducing apparatus



Sept. 29, 1931. A. J. CAWLEY SOUND RECORDING 0R REPRODUCING APPARATUS 1921 4 Sheets-Sheet l Original Filed Jan.

INVENTOR ALOYSlUS J. CAWLEY Lava, I ATTORNEY Sept. 29, 1931. A. J. CAWLEY SOUND RECORDING OR REPRODUCING APPARATUS Original Filed Jan. 8, 1921 4 Sheets-Sheet 2 ATTORNEY INVENTOR ALOYSHIS J. CAWLEY BY M Sept. 29, 1931. A. JJCAWLEY SOUND RECORDING OR REPRODUCING APPARATUS Criginal Filed Jan. 8. 1921 4 Sheets$heet 3 H H U H U H U .n U H U n U H U F L U U r H U H .n U U H U H U H U n U H U H U |..\\|\/L-/L M [1 INVENTOR ALOYSHJS J. CAWLEY BY 7 ATTORN EY Sept. 29, 1931. A. .1. CAWLEY 1,825,440

SOUND RECORDING 0R REPRODUCING APPARATUS Original Filed Jan. 8, 192} 4 Sheets-Sheet 4 INVENTOR ALOYSIUS J. CAWLEY ATTORNEY ir/crown:

Patented Sept. 29, 1931 Q'Jiii oil PATENT OFFICE ALOYSIUS J. CAWLEY, OF PITTSTON, PENNSYLVANIA, ASSIGNOR TO RADIO CORPORA- TION OF AMERICA, A CORPORATION OF DELAWARE SOUND RECORDING R BEPRODUCING APPARATUS Original application filed January 8, 1921, Serial No. 435,984. Divided and this application filed September 16, 1929. Serial No. 393,073.

This application is a division of my application Serial Number 435,984, filed January 8, 1921.

The invention relates generally to the method of producing sound records on motion picture films, so that sound and picture records may be synchronously reproduced, although the invention is not necessarily limited to this field.

More particularly, the invention is concerned with the recording of sound on a motion picture film at a recording speed that is much in excess of the speed of the film. An arrangement is provided whereby a recorder contacts with a film, while moving in the opposite direction thereto. The recording speed is thus equal to the sum of the speeds of the recorder and film.

A plurality of recorders are employed, which contact alternately with separate portions of the film. These recorders are placed radially at fixed intervals, and one contacts with a record surface of a given length, while the film has actually passed through but a fraction of this length. The other recorder is then in a position to contact with an equivalent length juxtaposed to, or opposite to that traversed by the first.

An electrical or mechanical arrangement is provided whereby the recorders are thrown out of operation when not recording their own specific record groove.

Arrangements are described whereby any desired sound recording speed may be obtained without any increase in the speed of the film, by simply increasing the number and speed of the recording units.

The invention is perfectly adaptable to the standard motion picture film as it exists in practice at present, and is concerned with placing sound records on the margin, or margins of such a film. This is particularly feasible if mechanical sound grooves are used, as there is room for a very large number of such records. The latter may be placed on one margin only, or be distributed on both margins, as hereinafter described.

As the sound records are intended to be placed on the margins of the film, there is no interference of picture and sound record as would be the case, if for instance, the latter were placed across the reverse face of the film, as in such case, they would be proected upon the picture screen.

The invention, further, is not limited to mere mechanical methods of recording, but is adapted to any means, such as photographic, magnetic, or the electrical reproduction described in another application. Although the invention is not limited to any of those methods, great emphasis is placed on the method employin electrically operated sound recorders and reproducers; the recording speed that it is most desired to use with this is approximately double the film speed.

It will be noted that there are no abrupt changes in the direction of moving parts. All parts move in a uniform manner, and the apparatus as a whole is very simple. It is to be especially noted that, although the recording speed is rather high, neither the film carrier nor the recorders move at this speed, the high speed mentioned being due to the relative motion of recorder and film. This means that considerable wear is saved in the apparatus.

One can readily see that by employing a suitable number of recorders moving at a proper speed, that photographic sound recording processes requiring a speed of six feet per second may be utilized so that they may be placed on a film that is moving at the standard motion picture speed of one foot per second.

For a more complete understanding of the invention, reference is to be had to the following description and claims taken in connection with the accompanying drawings, in which like characters of reference denote corresponding parts in all the views, and in which,

Figure l is an elevation View showing an electrical reproducing device.

Figure 2 is a cross sectional view on line BC of the rotating film carrier.

Figure 3 is an elevational view of an electrically operated, mechanical sound recorder placed on a radial arm.

Figure 4 is a plan view of a photographic 1M sound recorder placed on a radial arm also illustrating the detachable nature of the latter.

Figure 5 is a plan view of a device employing mechanical recording, whereby the non-functioning recorder is raised from the film surface at the proper time.

Figure 6 is a side view of a mechanical recording arrangement.

Figure 7 is a view showing the radial arms, stationary cam and contacts for raising recorder from film surface.

Figure 8 is a plan view of the disk attached to the hollow tubes, showing the passage in the valve body above.

Figure 9 is a cross sectional view of the valve body, showing the communicating passages made with the tubes below.

Figure 10, a and b, are diagrammatic views showing the arrangements of three and four recorders, respectively.

Figure 11 is a diagrammatic view showing two recorders adapted to play on each margin of the film.

Figure 12 is an elevational view showing the recorder diaphragm placed at the center of' the revolving element, with styli extending as radial arms.

Figure 13 is an elevational View, partly in cross-section, of another embodiment of the invention. This consists of two concentrically revolving sound recorders adapted to coact with circumferential valves.

Figure 14 is a side elevational view of the device shown in Figure 13.

Figure 15 is an elevational View of a sound box capable of use in thedevice of Figure 14.

Figure 16 is an plan view of a motion picture film having a plurality of high speed sound record grooves on its margin.

Figure 17 is an elevational View of a sound box also intended for use with the device of Figure 14.

Figure 18 is a plan view of an arrangement for rigidly connecting and moving wheel 1.

Figure 19 is a diagrammatic illustration of a reproducing apparatus provided with an amplifier and in cooperative relation to a projection screen.

Figure 20 is a diagrammatic illustration of the arrangement of apparatus for recordmg.

Figure 21 corresponds to Figure 1 but includes the photoelectric reproducer of Fig ure 4 and additional means for supporting the film.

Figure 22 corresponds to Figure 16 but shows the film as having two photographic sound records instead of four grooves.

There are many ways of carrying out the invention, and although certain structures will be described in detail, the invention is not limited to them. The film A is passed around the large sprocketwheel 1, contact roll 10 holding it in engagement with sprocket teeth 11, as shown in Figure 1. The member 1 is obviously not necessarily a wheel, but may be a drum or cylinder as shown in Figs. 13, 14 and 17, or any equivalent cylindrical member. The film then passes over a smaller sprocket 13, to which is rigidly attached the gear wheel 5. It is obvious that sprocket 1 pulls the film forward. \Vheel 5 communicates motion through wheel 4 to wheel 3, which is rigidly attached to shaft 14, which carries the radial arms 2, also rigidly attached to it, and bearing recording or reproducing means at their extremities. Toothed gear wheels 8, 4 and 5 are so proportioned that the devices at the extremities of the radial arms move, while in contact with the film surfaces, at a speed which is equal to (when two arms are employed) that of the film, but in the opposite direction. Obviously, the relative speeds of film and recorder passing over it, will be equal to the sum of their individual speeds. Consequently, if the speed of the film is one foot per second, the recording speed is twice this, or two feet per second. One can readily see that if the gearing is so arranged that the recorders move at a speed double that of the film, and three recorders are used, three records will be impressed, and the recording speed will be three feet per second. Four recorders with a speed of three feet per second would mean a recording speed of four feet per second, and so on.

It is obviously necessary to employ some means whereby only that recorder that is actually impressing its own specific record is in actual operation at any given time, all others being temporarily eliminated from activity. A very satisfactory method of accomplishing this is by the use of electricity, and this will now be described. Other methods will be described later. For this purpose, the commutator 6, Figure 2, is adjustably attached to the shaft, by means of set screws, or the like in such a position that brush cuts out of circuit-the recorder or recorders not functioning, and connecting only the recorder that is functioning. The commutator is shown in this case provided with two segments, 6a. and 66 one being attached by wire 9 to the device at the extremity of one radial arm, and the other attached by wire 8 to the other recording device. The wire 9 passes through shaft 14 which may be provided with suitable conducting passages 9a. In the drawings, the radial arms, shaft, etc., form part of the circuit, in which case only one brush 7 is necessary.

-In Figures 1 and 2, the radial arms 2 are provided with simple electrical contacting brushes, for the purpose of electrically resound record may be attained.

producing a photographic sound record as described in my Patent Number 1,698,536. The two contact brushes are shown at 15. Figure 3, however, shows a radial arm provided with an electrically operated, mechanical sound reproducer 17, provided with the stylus 18. The wire 8 and the metal body of the apparatus connects this device with the external reproducing circuit.

However, wires may be used throughout for the circuit connections, and also more than one brush may be used in connection with the commutator. Besides the adjustment of the position of the commutator on the shaft, obviously the brush 7 may be attached to a movable support, as is usual in electrical machinery, whereby it also may be moved to the most favorable position to obtain the best results.

The operation of the apparatus is perfectly simple. A device similar to that shown in Figure 1 may be attached to a camera or projector, and so connected that sprocket 1 is driven at standard motion picture feed, whereupon the recorder or reproducer will move in the opposite direction at the same speed (if but two recorders are used), with the result that the recording or reproducing speed is double that of the film, or about two feet per second.

The large sprocket wheel 1 is not fixed to the shaft 14:, but is permitted to revolve freely upon it, and is held in position by the disks l2 and 12, which are fixed firmly to the shaft, and which allow just sufficient play to let wheel 1 revolve freely without vibration. In the drawings, this wheel is shown as being driven by proper gearing.

Strong emphasis is placed on the recording or reproducing apparatus, of which Figure 3 is an illustration of the reproducer. This consists of a stylus operated by a telephone receiver to produce the sound record, and a stylus operating a microphone to reproduce it. This arrangement permits of electrical connections throughout, permitting the use of a commutator, as well as the actual reproduction of the sound record at a distance from the reproducer 54, Fig. 19, such as for instance at a projection screen 51. Moreover, the use of microphones 58 or the like in the camera 57 permits the use of special electrical apparatus 55, not otherwise available, whereby amplification of the Such amplifying means 53 are also available in the reproduction of the sound record by the reproducing apparatus indicated at 5 1, Fig. 19. The alternate connecting and disconnecting of the recorders is also more effectively accomplished by the employment of an electrical commutator. The set screw 16 rigidly fastens the disk 12 to shaft 14. Recorder 17 is detachable from the radial arm.

Figure 4 shows a photographic recorder 21, consistin of a small tungsten incandescent tubu ar lamp attached to the extremity of the radial member. It is firmly held in position by the screw 19, while electrical connection is made by the wire 8 and conducting metallic body of the arm. The radial arm may be detached from the disk by unscrewing the threaded end 20 out of the corresponding socket. Any type of sound recorder may thus be attached to the radial arm. The term radial member may be construed to mean not only the mechanical device but also a device that is partly made up of a light beam, which is directed by proper apparatus toward the moving film to chemically alter it. One readily sees that the invention is not concerned with any specific type of sound recording, but with a means of recording sound at a speed that is greater than that of the moving medium upon which the sound is recorded.

If it is desired to record or reproduce without the use of electricity, recourse may be had to the device illustrated in Figures 5, G and 7. Here the film is wound upon the revolving film carrier as before. The shaft 11 is made hollow. The recorders 22 connect with the hollow shaft by means of the hollow radial members 23, having the flexible element 24, which may be either a section of rubber tubing or the like, or a sliding joint; this is desi ned to permit of the recorders 22 being lifted in turn from the surface of the film, by operation of the connections 25 provided with the shoes 26, which coact with the stationary cam, 27. The cam is stationary, while the arms revolve. Gear wheel 3 is attached to the shaft 14, which is provided with the passage 34:. External connection is made by means of a swivel or other flexible joint, which permits turning but is sufiiciently sound tight. The action of spring 28 holds the shoes 26 in firm contact with the cam 27. lVhcel 1 moves the film and toothed gear wheel 3, 4 and 5 move the radial members in the opposite direction as in Figure 1. It is to be understood that actual contact with the film is only made through part of the circumference of film carrier 1, namely the lower part shown in Figure 6. The radial member lifts the recorder completely away from the film surface when it reaches the upper part of the circumference, as shown in Figure (3; no trouble is occasioned by the ravelling and unravelling of the film at the point where they leave or arrive at the rotating member. The exact contour of the cam shown is not implied in the drawings, as it may be made in many forms other than that shown at 27, Figure 7.

Another modification, whereby the film is in contact with both recorders or reproducers at all times, commutation being made by means of a valve arrangement, is shown in Figures 8 and 9. A. disk 30 is rigidly attached to the radial arms 23, and communicates therewith by means of the openings 31. Above this disk is placed the stationary valve body 33 having the passage 32 located directly over the disk 30. Passage 32 communicates with sound tube 34. Tubes 23 are isolated from each other by diaphragm, or partition 35. Moreover, those tubes are rigidly attached to shaft 14 as above described. It can be readily seen that as the radial tubes revolve together with disk 30, openings 31 communicate alternately with passage 32, so that at any given time, but one sound device is recording or reproducing. In other words, only the functioning recorder is in action.

Many other mechanical arrangements are possible, but it is not deemed necessary to illustrate them here. WVhere the radial members are made up of reciprocating parts, it is best to provide guides as shown at 29. Figure 10, a, illustrates diagrammatically the arrangements of the radial members when three are used, the speed being double that of the film by suitable gearing; the recording speed is thus three times the film speed. Figure 10 7) illustrates the arrange ment diagrammatically when four radial members are employed; their speed is three times that of the film the recording speed being four times that of the film. Figure 11 is also a diagrammatic view showing a method of using four radial members, two being on each side of the film and co-acting therewith; the recording speed in such case is also four times film speed. Figure 12 illustrates the fact that the recording diaphragm may be located at the center of the revolving film carrier, while the styli extend as radial arms. A type of sound recording employing centrally located sound boxes and circumferential valves is described in Figures 13 and 14. Figure 13 is a view of a device in which two concentrically revolving sound recorders are provided with two styli each, the latter being attached by means of bars 38 and 38 that possess greater flexibility towards their centers in one plane only, while being perfectly rigid in a plane that is at right angles to this. The stylus bars carrying the styli 18 and 18 do not vibrate in the plane of their circular motion, but may be readily vibrated in a plane at right angles to this, due to the stylus bar being flattened or thinned in the plane of motion of the bar. As shown in the drawing the stylus bars 38 and 38 are at right angles to each other; this, however may be varied. The valves in the apparatus are shown at the surface of member 1; several may be arranged circumferentially so that only one recorder is connected to the external circuit at a time. All reference numerals have the same meaning as heietofore,

and in addition, 36 and 36' represent two of the radial valves. 37, 37' are passages through 1 connecting the recorders with the valves at the proper time. The special stylus bars are shown at 38 and 38. These may also be jointed, if desired. The diaphragm 54 is connected to the stylus bar 38' by link The styli and film carrier move in opposite directions as before described, the commutation being made by means of the valves 36 and 36, which are movable over the surface in order that they can be disposed so as to permit but one recorder to record or reproduce its own record.

In Figure 14, which is a View of the left side of Figure 13, it will be noticed that passage 37 is just ceasing to give the record from its sound box, while 37 has just started to give its record. The opposite ends of the passages have been closed by film A. Passage 37 is communicating with opening 40, which extends for a distance of one-twelfth of the circumference of wheel 1; therefore, its corresponding stylus 18 (Figure 13) is about to sweep from 37, in the lower part of the circle, to wheel 10 during the same time that passage 37 traverses the opening 40. Although stylus 18' in the right horizontal position will pass from wheel 13a to 37" during the same period, its sound will not be heard because passage 37 will not reach the valve opening 40" in the upper right quadrant of the circle until stylus 18 has reached the position of 37' in the lower semicircle. It will thus be seen that the are extending from the point 37 in the lower semicircle to wheel 10 is the portion of the film where the sound is recorded or reproduced, the film passing through one-third of this arc, while the stylus passes over its entire length in the 0pposite direction. The sum of the speeds is four times film speed. If desired, the wheel 13a may be placed at 37, but in such case the are between these two points should be covered by the surface of the valve, as shown in the upper semi-circle between the valve openings. This is to prevent the escape of sound to the external air. It will be noticed that film a covers one end of passages 37, 37" and 37, while the passage 37 communicates with the openings in the Valves, such as 40. Also, since the film is held perfectly tight by means of wheels 10 and 13a, it will act as a spring to hold the stylus and film in contact, and it may be unnecessary to provide springs, or the like on arms 38, etc., to hold the two in contact. There is no objection to the overlapping of records, as it only means that the two records repro- 'duce the same sounds in synchronism for a short interval. In fact, this may be very desirable, as then it would compensate for the partial opening produced as at 37 communicating with 40. In this way, the two passages, such as 37 and 37 in Figure 14 would reproduce in synchronism until 37 had achieved a full, open communication with -10, at which time 37 would be completely cut off from its corresponding opening 10. There will thus be a fusing together of the separate records, which will act to disguise the disconnected character of those elements and give the illusion of a single continuous record. Obviously there will always be the same area of sound passage communicating with the valve openings; when one is three quarters open, the other isone-quarter open, and so on. \Vhen one attains its full opening, the other is closed. One goes from zero to maximum during the same time that the other goes from maximum to zero. This feature will occupy the same position in fusing the separate elements into one as the persistence of vision of the optic nerve occupies in fusiing the separate pictures of a motion picture The sound box l'fia for use with Figure 14 is shown in detail in Figure 15. Its sides may be entirely open as shown, while it rotates snugly in its chamber in wheel 1. The selection of the record is controlled entirely by means of passages 37, 37 37 and 37 coacting with openings 40, 40 and 40". As described above, only one passage can communicate with an opening at any one time. Or, the sound box may be partly closed and provided with suitable openings, such as 39 in Figure 17. These will communicate with passages 37 and 37', etc., only when desired, and will aid in giving a more hasty closing of passages 37 and 37. All of those figures merely illustrate different ways in which the fundamental principles underlying the invention may be carried out. The invention embraces them and many other modifications.

If the photographic method of reproducing is used, the selenium cell or equivalent 63, Fig. 21, can be made in the form of slit arranged in a semi-circle, corresponding to the form of the curved film. The effective part of the cell will be thus in the form of a long, narrow slit over which the light recorder on the radial arm 62, illustrated in detail in Fig. 4. passes longitudinally. Consequently, as the light is not stationary, a heat-absorbing means will be unnecessary.

By making the rotating film carrier 1 of very large diameter, the styli would remain in contact with the. film for a much longer period. Also the possibility of the commutation of the different reproducers being audibly detected by the audience would be minimized.

Each recorder contacts with the precise portion of the film as regards right or left throughout the length of the film. As the .JULM um latter is held rigidly in position, the proper sound reproducer finds its corresponding groove with absolute precision.

By making shaft 14 sufliciently long and adding one or more extra arms similar to 2 and 2 and spacing them equi-distantly on the shaft, and changing the gearing to ro tate them at the proper speed, which is a multiple of the film speed, the sound recording speed is thus increased. The electrical connections and commutator must be also adjusted to correspond. The flexibility of the mechanism is obvious.

In order to offer a firm support to the film while the recorder or reproducer is passing over its surface, an endless belt 67, Fig. 21, made of a substance approximating the density of ordinary phonograph record backing material, such as waxed paper, may be arranged so as to pass around the contact roll 10 and sprocket 13. This belt may be provided with a slack adjuster or idler consisting, for instance of a weighted pulley 71, the weight being indicated at 72.

Wheels 3, 4 and 5 are supported on any suitable frame work 61. Power is preferably applied to 1, so as to move the film at standard motion picture speed.

Photographic sound recording has been very successful commercially, and as there is room for many such records on the margin of a moving picture film, the invention offers a means of placing several such records there and utilizing them to reproduce sounds. Moreover, by this means a recording speed is available that is in excess of that used in commercial sound recording.

An advantage of electrical commutation is that a record can come into contact with the film for a time before it is actually brought into electrical connection.

Having thus described my invention, I claim as new and desire to secure by Letters Patent.

1. In sound reproducing mechanism, a film having an optically varying sound record thereon, a reproducenrotary supporting means for moving the film, means for maintaining the film on the supporting means with the sound record portion extend ing unsupported beyond the edge thereof, and means for driving said wheel, whereby said film will be driven at a uniform speed.

2. In an apparatus of the class described a wheel adapted to support a film having a sound record adjacent to the edge thereof with the sound record portion of the film extending beyond the edge of said wheel, said wheel being relatively large, sound reproducing means in cooperative relation to the sound record on said extending edge, and means for driving said wheel.

3. In phonographic apparatus in which the sound record is formed on a film constituting an elongated carrier, the combination of the wheel, means for rotating said wheel at uniform speed, means for feeding the film upon said wheel at one point and off therefrom at another point and causing it to adhere closely thereto without slippage between said points, and means, between which and the record carrier acoustically modulated energy is transferred, as the carrier moves past the same, coacting with the car rier when at a position on said wheel intermediate said two first named points.

4. In phonographic apparatus in which the sound record is formed on a film, the combination of a cylindrical member, means for rotating said cylindrical member at uniform speed, means for feeding the film upon said cylindrical member at one point and ofi' therefrom at another point and causing it to adhere closely thereto without slippage between said points, and means, between which and the record film acoustically modulated energy is transferred, as the film moves past the same, coacting with the film when at a position on said cylindrical member intermediate said two first named points.

5. In phonographic apparatus in which the sound record is formed on a film, the combination of a cylindrical member, means for rotating said cylindrical member at uniform speed, means for feeding a record film onto said cylindrical member at one point and ofi therefrom at another point and cansing the film to adhere closely to the cylindrical member without slippage between said points, said film record being arranged to overhang one side of the cylindrical member, and sound reproducing means positioned inwardly of the overhanging position of the film.

ALOYSIUS J. CAWLEY. 

